Identification and characterization of the lysobactin biosynthetic gene cluster reveals mechanistic insights into an unusual termination module architecture

Chem Biol. 2011 May 27;18(5):655-64. doi: 10.1016/j.chembiol.2011.02.012.

Abstract

Lysobactin (katanosin B) is a macrocyclic depsipeptide, displaying high antibacterial activity against human pathogens. In this work, we have identified and characterized the entire biosynthetic gene cluster responsible for lysobactin assembly. Sequential analysis of the Lysobacter sp. ATCC 53042 genome revealed the lysobactin gene cluster to encode two multimodular nonribosomal peptide synthetases. As the number of modules found within the synthetases LybA and LybB directly correlates with the primary sequence of lysobactin, a linear logic of lysobactin biosynthesis is proposed. Investigation of adenylation domain specificities in vitro confirmed the direct association between the synthetases and lysobactin biosynthesis. Furthermore, an unusual tandem thioesterase architecture of the LybB termination module was identified. Biochemical characterization of the individual thioesterases in vitro provides evidence that solely penultimate thioesterase domain mediates the cyclization and simultaneous release of lysobactin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Bacterial Proteins / genetics*
  • Bacterial Proteins / metabolism
  • Base Sequence
  • Depsipeptides / biosynthesis
  • Depsipeptides / genetics*
  • Lysobacter / enzymology
  • Lysobacter / genetics
  • Molecular Sequence Data
  • Multigene Family
  • Peptide Synthases / genetics
  • Peptide Synthases / metabolism
  • Thiolester Hydrolases / genetics
  • Thiolester Hydrolases / metabolism

Substances

  • Bacterial Proteins
  • Depsipeptides
  • Thiolester Hydrolases
  • Peptide Synthases
  • katanosin B

Associated data

  • GENBANK/JF412274